Health Committee on May 25th, 2020

[Dr. Gerry Wright]

I'd be very happy to, and again, let me reiterate how grateful I am that we were able to get that money out very quickly, as both other witnesses mentioned.

You were talking about collaboration earlier. This is a collaboration between a virology lab headed by Dr. Matt Miller in our institute, as well as a human cellular biologist, Dr. Mike Tyers, who's at the Université de Montréal. We're trying to tackle the problem by finding drug candidates for the virus itself, as well as to address issues such as entry of the virus into cells, so we can think of drug cocktails to be able to kill the virus and prevent infection.

At McMaster, we have a small drug discovery platform, very similar to what you'd find in the pharmaceutical industry, which we've developed over the years with the support of federal and provincial governments. That's what we're deploying to be able to do this, to tackle at once the virus and the human cells on the other side, and because of the advances that Dr. Mossman's group has been able to make, we have SARS-CoV-2 in our biosafety level 3 facility and we're able to test those drug candidates on the virus directly.

[Tony Van Bynen, Liberal, Newmarket—Aurora, ON]

We know that handwashing is ideal, but it's not always available as an option when you don't have access to soap and running water, which means that you may not have any choice but to resort to hand sanitizers. I'd like to hear your thoughts on whether there's any way of avoiding antimicrobial resistance, but still protecting yourself from COVID-19.

[Dr. Gerry Wright]

Certainly. The best way to do that is to use hand sanitizers that have alcohol, and not other compounds that have the ability to select for drug resistance. As far as we know, alcohol-based hand sanitizers have no effect at all on selection for resistance. Those are the ones we should be using. They tend to be deployed in almost all health care facilities.

[Tony Van Bynen, Liberal, Newmarket—Aurora, ON]

Thank you.

[The Chair, Liberal, Ron McKinnon]

We go now to Monsieur Thériault for six minutes.

[Luc Thériault, Bloc, Montcalm, QC]

Thank you, Mr. Chair.

I'd like to thank all the witnesses for their insightful contributions to the hunt for solutions, because solutions are indeed what we are looking for. I'm going to set the scene. Then, I'd like Dr. Quach-Thanh and Dr. Tremblay to comment.

We still don't know much about the virus. We don't have a vaccine. Since the focus has shifted to reopening the economy, some people have told us that we're going to have to learn to live with the virus, much like we learned to live with AIDS. We're turning to antiviral drugs, but we don't have anything meaningful yet. What's more, we still haven't taken full advantage of serological testing. The country isn't self-sufficient. Various parts of the health care system shut down, only now starting to get back on track. Some health care settings have outbreaks. Front-line workers have had to stop working because they've been infected. Lastly, we know nothing about the quality and longevity of natural immunity.

With all those unknowns, it feels as though we have no choice but to buy time to lessen the impact. That's what is referred to as flattening the curve.

What's the safest pace for easing restrictions?

Is Quebec on the right track, or is it following the path taken by countries that have had to shut things down again?

[Dr. Cécile Tremblay]

As for an appropriate pace, I would say the conditions set out by the World Health Organization, or WHO, for lifting restrictions are appropriate. They include a decline in the number of new cases for a period of at least 14 days and the capacity to test people and prevent the movements of incoming travellers.

In Quebec, two different epidemics are at play: the one affecting the greater Montreal area and the one affecting the rest of Quebec. The WHO conditions were met in the rest of Quebec, meaning, outside Montreal. However, in Montreal, that's taken more time. Although we are now seeing a slight decline, it's actually more of a plateau.

If the easing of restrictions that began today isn't done in an orderly way, there is a risk that the daily number of new cases could be higher than we'd hoped, which could spark new outbreaks and infections more easily.

Overall, then, I think things have been handled well, in that the government waited until certain conditions were met before it began lifting restrictions. As for Montreal, it will be necessary to keep a very close eye on what happens in the next few weeks.

[Dr. Caroline Quach-Thanh]

I completely agree with Dr. Tremblay. Paying special attention to the situation in Montreal will be crucial. Things are relatively stable in the rest of the province, but the situation isn't the same throughout the Montreal area. The virus has unfortunately stigmatized the most vulnerable segments of the population, highlighting existing social inequalities. Some parts of Montreal are more affected than others.

One of the reasons why the government eased certain restrictions is that people were going out anyways. Knowing people had already started going out, the government thought it better to control, to some extent, the lifting of restrictions than to tell people to keep staying home. That's certainly not without risk, so it'll be important to pay close attention to what happens over the next two weeks.

[Luc Thériault, Bloc, Montcalm, QC]

It's a matter of buying time. We're still not self-sufficient when it comes to producing personal protective equipment. Outbreaks have hit hospital centres and long-term care facilities.

We're still looking at a second wave. At one point, we thought we'd be ready for the second wave. Is there a risk of people coming out of lockdown on their own initiative? Are you worried about people self-lockdown-lifting, so to speak? We don't have much time left, perhaps three months until the second wave is expected to hit.

[Dr. Caroline Quach-Thanh]

We are trying to buy time. You're right; the second wave is likely to occur in the fall, when kids go back to school and normal activities will have resumed. Until then, reducing close contact with people is a must.

We've learned that the virus spreads when people are in relatively close contact for a relatively prolonged period, so it spreads much more effectively indoors than outdoors. It's probably relatively safe to let people go outside, but they need to stay two metres apart, as much as possible. Even when people are a metre or a metre and a half apart, with dilution, warmer weather and humidity, the virus is a bit less resistant, so it shouldn't be transmitted as easily.

I think people need to get used to wearing a mask in public, but not necessarily outdoors. Wearing one in confined spaces where people can't stay two metres apart the entire time is definitely necessary.

As you said earlier, we have to learn to live with the virus, because it's here to stay in the short term. We have to wait until a drug or vaccine is available in order to protect the entire population.

We know transmission is going to occur, but we have to find ways of reducing it as much as possible. We don't want to have to force people into lockdown all over again because transmission has picked up too much.

[Luc Thériault, Bloc, Montcalm, QC]

Are you optimistic about—

[The Chair, Liberal, Ron McKinnon]

Thank you.

Mr. Davies, please go ahead for six minutes.

[Don Davies, NDP, Vancouver Kingsway, BC]

Thank you, Mr. Chair, and thank you to all the witnesses.

To whichever witness feels best qualified to answer, what is the most current state of knowledge and information concerning immunity? Are we getting closer to understanding whether or not, once we're exposed, immunity is conferred, and if so how long might that be for?

[Dr. Cécile Tremblay]

I can start and others may add.

Right now what we know is that most people who have been infected will develop some kinds of antibodies. The amount of antibodies and the quality of these antibodies are not known for sure. They may vary from one person to the other. They may vary on the type of exposure a person has had, whether they've had a severe disease or whether they've had a mild disease, in which case they might not mount a very big immune response.

The jury is still out in terms of the quality of the immune response as to whether it is really very protective against reinfection. We can assume that probably it would be somewhat effective against reinfection.

What is less known is the durability of this immune response, of these antibodies. From a recent study that was published last week, immune responses were evaluated over a period of 35 years in 10 individuals, and all their coronavirus infections were mapped. The conclusion was that the lasting immunity against a coronavirus infection was between six to 12 months.

This is a problem because it's not a very long-lasting immunity. If we want to rely on herd immunity, it would take forever for a society to be 70% totally immune against these types of viruses. That's where we are right now.

[Don Davies, NDP, Vancouver Kingsway, BC]

Thank you.

I'll direct another question to you. On May 7, you called the failure to test people who might be asymptomatic COVID-19 carriers a missed opportunity. Given that epidemiological modelling has suggested that asymptomatic or preclinical cases may be responsible for potentially significant transmission of the virus, what do you think when the Government of Ontario and I think even Quebec have so far declined to test asymptomatic individuals? What would be your comment on that?

[Dr. Cécile Tremblay]

For the last week or so in Quebec, since they've increased the testing numbers, they have allowed for testing of asymptomatic individuals.

There are two ways of seeing this. If you go randomly in the population and test anybody who's asymptomatic, it's not really worth it, because you're not going to find that many who are positive, so that is not a good way to go. On the other hand, if you have a person who is infected and has several contacts, some of whom are asymptomatic, I believe they need to be tested, and it is very important. It should have been done earlier, in my opinion, testing the asymptomatic contacts of symptomatic people.

[Don Davies, NDP, Vancouver Kingsway, BC]

Thank you.

Again, generally to everybody, I'm interested in the most current state of knowledge on transmission. We know that COVID—I should call it SARS-CoV-2— is definitely transmitted by droplets.

What do we know right now about its transmission by aerosol or fomites?

[Dr. Caroline Quach-Thanh]

I'll take this one, if you don't mind.

What we know is that, in certain circumstances, particularly when you're in a hospital and you do medical procedures, you might be able to aerosolize that virus. For instance, if you intubate a patient, if a patient is on CPAP, when you go in the airways, we know that it aerosolizes the virus. That's why we put them in negative pressure rooms. We wear N95 masks and all the rest.

What is still not completely clear is what happens when a person coughs or does physical activity and breathes out very strongly. I think that what seems to happen is that you are able to have smaller droplets that will be suspended in the air for five to eight minutes, but it's not per se for now in aerosol.

Studies are currently ongoing, particularly in long-term care facilities where we're all wondering if airborne transmission is not happening, given the proportion of people who become infected when they just go into those facilities. Air sampling is being done with cultures of air. We know that we are able to find pieces of viruses in the air in long-term care facilities, but we don't know if that's a piece of a virus that's dead or if it's a virus that's still able to replicate.

The studies are ongoing right now, and I think we'll have the results within the next month or so. At that point in time, we'll know. At this point in time, I think daily living will cause droplets that may be suspended in the air for five to eight minutes, like when you sing, for instance, and when you cough very hard, and that is still able to infect the next person. Aerosolization per se for now is not yet approved upon.... The jury is still out, as Dr. Tremblay would say.

[The Chair, Liberal, Ron McKinnon]

Thank you.

We'll start round two with Mr. Jeneroux. Please go ahead for five minutes.

[Matt Jeneroux, Conservative, Edmonton Riverbend, AB]

Thank you, Mr. Chair.

Dr. Tremblay, if you can get a good idea of what our national stockpile looks like, please share. We've certainly tried to get that information over and over again at this committee. Perhaps it's something we can follow up on after this meeting.

The question I want to ask, and I'll probably start with you, Dr. Tremblay, is a follow-up on the question my previous colleague just asked with regard to immunity. The question we receive often is whether people build immunity to the virus once infected.

In a bit of a different angle to what my colleague asked, has there been any progress in answering that specific question and have we seen an example of people becoming reinfected with COVID-19?

[Dr. Cécile Tremblay]

A lot of labs are working on that to evaluate the quality of the immune response. We can take for granted that there is some kind of immune response and some antibodies are being made following infection. We just don't know exactly the quality and the strength of these antibodies. Are they neutralizing antibodies, the kind of antibody that can really kill the virus when they meet the virus again, or are they just binding antibodies? We still don't have the answer for that.

As far as being reinfected, there have been a few case reports suggesting that some people might be reinfected. We don't know so far and we think it's most probably a person who had been infected. The virus was not totally eliminated from their body although they were not detectable in a couple of PCR tests, and then a few weeks later, they become detectable again. Most likely it's the same disease, but to date we haven't had a study that can definitely rule out that there hasn't been any reinfection. If it is, it is rare.

[Matt Jeneroux, Conservative, Edmonton Riverbend, AB]

Would any other witnesses like to weigh in on the ability to build immunity to the virus?

[Dr. Caroline Quach-Thanh]

As Dr. Tremblay just said, there are still so many unknowns around this virus. We know there is an antibody response, but we don't know how long that will last. If you were to look at the last rapid-response COVID-19 CIHR grant, you'd find a couple of people putting that particular question in so that we are able to actually have an answer to it.

Again, as Dr. Tremblay said, most of the people we've seen with relapse, positive PCR, were likely the same patients with undetectable PCR who became positive again. We had a patient like that. They were positive for 65 days, with one bit in between that was negative and where the virus never grew.

We're not exactly sure why this virus hangs around for so long, but it does. It doesn't mean people are still infectious, though.

[Matt Jeneroux, Conservative, Edmonton Riverbend, AB]

We keep hearing that until there's a vaccine, normal life in terms of social distancing won't...or we'll have to keep up the social distancing. Is there another path that you guys can see without a vaccine—I already see a few of you shaking your head—where we can relax some of the social distancing?

[Dr. Caroline Quach-Thanh]

Well, you can, but then what happens is that you will have a huge wave. Your health care system will be overwhelmed and you will look like the U.S. or Italy. Yes, there's always a way around it, but until we have a vaccine, or we reach herd immunity, which will not come anytime soon, you have to maintain physical distancing, at least, if not social. Otherwise, we'll transmit it to one another.